Conveyors



Feb. 20, 1962 F. L. HOPKINS ETAL 3,021,939

coNvEYoRs Filed Aug. 15, 1955 2 Sheeizs-Sheei'I 1 Feb. 20, 1962 F. L. HOPKINS ETAL 3,021,939

coNvEYoRs Filed Aug. 15, 1955 2 sheets-sheet 2 INVENTORS FFAA/K /loPK/A/s United States Patent G l 3,021,939 CONVEYORS t Frank L. Hopkins and Harold K. Fox, Minneapolis, Minn., assignors to Bemis Bro. Bag Company, Minneapolis, Minn., a corporation of Missouri Filed Aug. 15, 1955, Ser. No. 528,467 3 Claims. (Cl. 198-131) This invention relates to new and useful improvements in conveyors, and more particularly to so called endless conveyors which comprise a load-carrying surface adapted to receive and transport commodities, such as filled bags, etc., from one place to another. An object of the present invention is to provide such an apparatus wherein the load-carrying surface is more or less open to permit spillage dropping onto the conveyor when filling bags and the like, to pass directly therethrough onto the floor beneath the filling station, or into a suitable receiving means, and thereby prevent such spillage from being carried along with the conveyor and dropped onto the floor along the length thereof.

Av further object of the invention is to provide a conveyor of the class described, wherein spillage or material overflowing from the bag tops, when the bags are filled is precipitated directly onto a given place or surface beneath the conveyor whereby unsightly accumulation or deposit of the material on the fioor along the length of the conveyor cannot occur.

A further and more specific object of the invention is to provide a conveyor particularly designed for transporting large iiexible walled bags orl containers having their bottom ends clos-ed' by bringing the marginal edges of the opposed bag body walls into contacting relation with one another, and suitably securing them together, as by stitching, and/ or folding a sealing strip or band over the flattened bag bottom walls and adhering it thereto, whereby the bag bottom has a natural tendency to become V-shaped in configuration, the load-carrying surface of said conveyor being V-shaped in cross-section to conform to the bag bottoms, whereby when filled bags are deposited on the conveyor, bag filling machine or packer, the bottom ends of the filled bags will settle snugly into the V-shaped carrying surface of the conveyor, whereby the bag bodies cannot relatively rotate upon the conveyor, nor are their lower ends likely to spread or expand when the filled bag bodies are dropped Vfrom the packer filling tube onto the conveyor. The V-shaped conveying surface also prevents the filled bag bodies from tilting sideways on the conveyor and assures delivery of the bag top into the bag top closing machine.

A further and more specific object of the invention resides in the unique construction of the load-carrying surface of the conveyor which comprises a plurality of spaced parallel bars which cooperate to form the load-carrying surface thereof, the ends of said bars being secured to a pair of endless chains having running connections with suitable sprockets at the ends of the conveyor frame, said bars being generally V-shaped, whereby the contour of the load-carrying surface of the conveyor conforms to the normal shape of the bag bottoms, to thereby prevent the filled bags from relatively rotating on the conveyor, and whereby the bags may more readily be accurately delivered to a bag top closing and sealing machine.

A further object of the invention is to provide a conveyor comprising a supporting frame having a pair of spaced parallel conveyor chains mounted thereon, and the load-carrying surface of said conveyor being composed of a plurality of spaced parallel bars having anti-friction roliers at their endsadapted to travel on suitable tracks, whereby the load being carried by said conveyor is supported on said anti-friction rollers and said tracks.

A further and more specific object of the invention is 3,021,939 Patented Feb. 20, 1962 ECC to provide a conveyor of the class described including a supporting structure comprising longitudinally extending frame members, the upper portions of which cooperate to provide longitudinally extending tracks adapted to support the anti-friction rollers provided at the ends of the transversely disposed V-shaped cross bars of the loadcarrying surface of the conveyor, whereby the conveyor, when loaded, may be operated with a minimum of power, a highly desirable attribute in an apparatus of this general type.

Other objects of the invention reside in the specific manner in which the anti-friction rollers are secured to the ends of the V-shaped load-carrying bars of the conveyor; in the construction of the supporting frame of the apparatus, which includes a pair of longitudinally extending channel members secured together in ltransversely spaced relation by suitable girts or tie members, said channel members being provided at each end of the apparatus with suitable supporting legs having their upper portions secured to the channel side frame members and their lower ends arranged to engage the floor; and in the simple and inexpen-sive construction of the apparatus as a whole, whereby the conveyor may readily be moved about from place to place as a unit.

These and other objects of the invention andthe means for their attainment will be more apparent from the following description taken in connection with the accompanying drawings.

In ythe accompanying drawings there has been disclosed a structure designed to carry out the various objects of the invention, but it is to be understood that the invention is not confined to the exact features shown, as various changes may be made within the scope of the claims which follow.

' In the drawings:

FIGURE l is a side elevational view of the novel conveyor herein disclosed;

FIGURE 2 is a top view of FIGURE l, showing the open load-carrying surface of the conveyor; and

FIGURE 3 is an enlarged cross-section view on the line 3 3 of FIGURE ll, showing the V-shaped contour of the load-carrying surface and a flexible bag body supported thereon.

The novel conveyor herein disclosed is shown comprising a suitable supporting frame comprising a pair of longitudinally extending side-frame members 2 and 3, preferably of channel cross-section, and having their upper and lower flanges 4 and 5, respectively, facing inwardly as best illustrated in FIGURE 3.

The side frame members Z and 3 are tied together transversely of the apparatus by a plurality of girts or tie members, generally indicated by the numeral 6 in FIGURE l. These tie members, as here shown, are tubular in cross-section, although not necessarily so, and are provided at their ends with securing plates 7 which are bolted or welded to the upright webs of the side channel members, thereby to provide a very rigid compositesupporting structure.

Plate elements 8 and 9 are secured to .the opposite ends of the side frame members 2 and 3, as shown in FIGUREl l, and cooperate to provide supporting legs for the conveyor frame toupwardly space the conveyor belt, subsequently to be described,I from the door or surface upon which the conveyor is positioned.

A cross shaft 11 is mounted in suitable bear-ings 12 at the discharge end of the conveyor and has secured thereto in laterally spaced relation a pair of sprockets 13. Endless `chains 14 have running connections with the sprockets 13. Secured to shaft 11 at the back side of the machine is a sprocket 1.5 which is driven by a chain .16 from a suitable speed reducer 17, shown directly connected to a motor 18.

Mounted at the opposite end of the supporting frame is a cross shaft 19l shown provided at its ends with transversely threaded bores adapted to receive adjusting screws 2l, rotatably supported in lugs 22 welded to the machine frame. The adjusting screws 21 serve to transversely adjust the shaft l19 in guide slots 23 provided in the legs or machine frame 9, thereby to take up slack in the conveyor belt, subsequently to be described. Rotatably mounted on shaft 19 are a pair of sprockets 24 which are axially retained in their proper positions on shaft I19 by suitable collars 25, secured to the shaft. In other words, the sprockets are mounted to idle freely upon the shaft 19, when the conveyor is in operation.

An importantfeature of the present invention resides in the construction of the load-carrying surface of the conveyor, whereby spillage and other material is not likely to accumulate thereon during the bag filling operation as is common with ordinary at belt conveyors. As best illustrated in FIGURES 2 and 3, the load-carrying surface of the conveyor is composed of a plurality of slats 26, disposed transversely of the conveyor in spaced parallel relation, and have their ends suitable anchored to the conveyor'chains 14. The slats 26 are V-shaped, asbest illustrated in FIGURE 3, and cooperate 'to provide the novelopen V-shaped load-carrying surface of the conveyor. The opposed end portions 27 of each slat 26 are horizontally disposed, as shown in :FIGURE 3 and extend outwardly over the upper flanges or tracks 4 of the side frame members 2 and 3` Angle brackets, generally designated by the numeral 28, are secured to the opposed end portions of each slat 26. Each bracket 2S has a vertical leg 29 and a horizontal leg 31, the ends of which are suitably secured to the inclined portions of the slats 26 by such means as welding, whereby the brackets 28 of each Slat 26 become an integral part thereof.

Means is provided for minimizing the drag of the upper loaded run of the conveyor, and comprises a plurality of anti-friction rollers 32. These rollers are rotatably mounted on studs 33 secured to the upright or vertical legs 29 of each bracket 28, and are adapted to travel upon the tracks 4 provided by the side frame members 2 and 3.

lT he horizontal legs 31 of angle brackets 28 are se'- cured to spaced links of the chains 14 `by such lmeans as bolts or studs 34, shown in FIGURE 3, whereby the the slats .26, brackets 28, and anti-friction rollers 32 become an integral part of the composite endless conveyor, featured in the present application.

Longitudinally extending angle iron guard rails 35 are provided over lthe horizontal end portions 27 of the slats 26 to prevent such ends from contacting the operators clothing. Rails 35 are supported on upright brackets or bars 36 secured to the channel side members 2 and 3 of the supporting frame.

The novel conveyor herein disclosed has been found extremely practical and eflicient for conveying filled bag bodies from one place to another, and particularly when the unsealed bag tops are to be fed through a bag top closing and sealing machine, as is customary. It is now quite common in the industry to close the open tops of large flexible walled bag bodies by pressing the walls of each bag top into atwiserelation and securing said walls together by stitching. To effectively and expeditiously close the bag tops by sewing, it is essential that the flattened bag top walls are accurately directed into the sewing head.

The present conveyor .is particularly applicable for such use in that the V-shaped cross-section of its loadcarrying surface prevents the bag bodies from relatively rotating on the conveyor, when being conveyed into and through the sewing head. The V-shaped cross-section of the conveyor also serves another purposev in that it substantially conforms to the shapek of the sewed bag bottoms which normally are V-shaped in formation. -The lower portions of the bodies of such bags are also usually oval in cross-section, and it is desirable to maintain such shape as it enhances the appearance of the filled bag bodies.

Thus, it will be seen that when filled bags of the type above described .are dropped from a filling tube onto the V-shaped load-carrying surface of the present conveyor, its V-shaped bottom will drop rmly into the trough-like contour of the conveyor, whereby the inclined bottom walls of the bag bottom will impinge against the inclined surfaces of the conveyor in such a manner that the entire lower portion of each bag body is so supported that it is not likely to spread or expand horizontally, which might seriously mar the general appearance of the filled bag body. f

The unique V-shaped formation of the load-carrying surface of the conveyor also tends to keep the filled bags in an upright position with the attened bag tops substantially aligned with the bag top sewing and closing mechanism, whereby the bag tops may readily be' accurately guided into the sewing head with the assurance that the bag tops will be uniformly and neatly closed. Thereafter an adhesive strip may readily and conveniently be applied over each sewed bag top to complete the closing and sealing thereof in such manner that finely comminuted material cannot sift from the Sealed bag tops through the needle holes made in the bag top walls during the sewing operation. The conveyor is also very quiet and smooth in operation, due largely to the fact that the load-carrying yslats travel over the tracks 4 on the anti-friction rollers 32. By thus supporting the slats 26, the chains 14 serve only topull the load along the conveyor, the entire weight of the bags being carried by the tracks 4 4 of the side frame members 2 and 3.

As hereinbefore stated, the use ofthe novel conveyor herein disclosed, all spillage of material at the bag filling machiner will drop through-the lconveyor onto the oor or into a suitable receiving means provided at the filling station', whereby such spillage cannot be entrained with the conveyor and dropped onto the floor along the length thereof. The upper surfaces of the V-shaped slats forming the load-carrying surface of the conveyor are oval or semi-cylindrical, thereby to prevent the accumulation of material thereon.

Suitable guards 37 and 38 are provided respectively at the receiving and discharge ends of the conveyor, as best illustrated in FIGURES 1 and 2.' These guards it Will be noted, extend outwardly beyond the V-shaped slats as they travel around the ends vof the conveyor, thereby to prevent clothing and other articles from accidentally becoming engaged with the ends of the V-shaped slats as they thus travel around the ends of the conveyor. Supporting angles or guide rails 39 are provided intermediately of the conveyor for supporting the lower runs of the conveyor belt, as best illustrated in FIG- URE 1. These angles or auxiliary rails may be suspended from the side frame members 2 and 3 by suitable brackets 41.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, but the appended claims should be construed as broadly as permissible in view of the prior art.

We claim as our invention:

l. In a conveyor of the class described, a supporting frame comprising inwardly facing longitudinal side members of channel cross-section, tie members securing together said side members in spaced parallel relation to provide a rigid unitary frame structure, leg means at the ends of said frame for upwardly spacing said side frame members from the floor, a drive shaft rotatably mounted in one end of said frame Iand having means for connecting it to a source of power, a pair of sprockets secured to saidshaft between said side frame members in proximity thereto, a shaft mounted at the oppo- E site end of said frame, a pair of sprockets rotatably mounted on said second shaft and cooperating with said first pair of sprockets to support a pair of spaced parallel endless chains, L-shaped brackets arranged in pairs transversely of the conveyor and having their horizontal legs secured to said chains at spaced intervals the lengths thereof, anti-friction rollers mounted on the vertical legs of said brackets for rotation about horizontal axes, the upper surfaces or" said side frame members providing longitudinally extending tracks for said anti-friction rollers to travel upon the length of the conveyor, a slat secured to each pair of L-shaped brackets, said slats cooperating to provide an open V-shaped loadcarrying surface for transporting large filled bags having V-shaped bottoms, said open load-carrying surface preventing spillage of finely disintegrated material from accumulating thereon, said anti-friction rollers and tracks carrying the weight of the load and said chains propelling the load along the conveyor, and means secured to the supporting frame and extending inwardly over the ends of said slats to prevent said ends from engaging foreign objects.

2. ln a conveyor of the class described, a supporting frame comprising longitudinally extending side members secured together in laterally spaced parallel relation, a drive shaft rotatably mounted in one end of said frame and having means for connecting it to a source of power, a pair of sprockets secured to said shaft between said side frame members, a shaft at the opposite end of said frame having a pair of similar sprockets mounted thereon, said second pair of sprockets cooperating with said rst pair of sprockets to support a pair of endless chains, a plurality of elongated V-shaped slats secured to said chains in cross-wise relation the length of the conveyor and disposed in closely spaced relation and cooperating to provide an elongated open non-yieldable load-carrying surface for conveying large flexible walled iilled bags, and upon which comminuted material or spillage cannot accumulate, means independent of said chains for carrying 4the weight of the load, a plurality of anti-friction rollers secured to the ends of said slats and arranged to travel on fixed tracks, a right angle bracket xedly secured lto each end of each slat with one of its legs vertically disposed and its other leg horizontally disposed, the vertical leg of each of said brackets having an anti-friction roller mounted thereon adapted for rolling engagement on said tracks, and the horizontal legs of said brackets having means for connecting them to said chains.

3. In a conveyor of the class describe-d, a supporting frame comprising longitudinally extending side members secured together in laterally spaced parallel relation, a drive shaft rotatably mounted in one end of said frame and having means for connecting it to a source of power, a pair of sprockets secured vto said shaft between said side frame members, a shaft at the opposite end of said frame having a pair of similar sprockets mounted thereon, said second pair of sprockets cooperating with said rst pair of sprockets to support a pair of endless chains, a plurality of V-shaped slats secured to said chains in cross-wise relation the length of the conveyor and disposed in closely spaced relation and cooperating to pro-- vide an elongated open non-yieldable load-carrying surface for conveying large flexible walled lled bags, and upon which comminuted material or spillage cannot accnrnulatc, means independent of said chains for carrying the weight of the load, a plurality of anti-friction rollers secured to the ends of the slats and arranged to travel on xed tracks, a right angle bracket iixedly secured to each end of each Slat with one of its legs vertically disposed and its other leg horizontally disposed, the vertical leg of each bracket having an anti-friction roller mounted thereon adapted for rolling engagement on said tracks, the horizontal legs of said brackets having means for connecting them to said chains, said slats being semi-cylindrical in cross-section, thereby to minimize the accumulation of spillage of material thereon.

References Cited in the tile of this patent UNITED STATES PATENTS 559,370 Dodge May 5, 1896 1,028,739 Kibat June 4, 1912 1,481,431 Plumb Jan. 22, 1924 1,501,817 Sevigne July l5, 1924 1,737,819 Wetmore Dec. 3, 1929 1,882,608 Howe Oct. 11, 1932 1,886,926 Walter Nov. 8, 1932 1,945,300 West Jan. 30, 1934 2,302,656 Dray Nov. 17, 1942 2,768,657 Kindseth Oct. 30, 1956 FOREIGN PATENTS 38,514 Denmark Feb. 24, 1928 

